TypeError: 'DeclarativeFieldsMetaclass' object is not iterable

Hello. I got TypeError: 'DeclarativeFieldsMetaclass' object is not iterable when I tried to register the form model in admin.py file.

the forms.py file:

from django import forms

class Person(forms.Form):
    fname = forms.CharField(label='first name',max_length=50)
    lname = forms.CharField(label='last name',max_length=50)
    age = forms.IntegerField(label='age',min_value=1,max_value=100)
    gender = forms.ChoiceField(label='gender',choices=[('female','female'),('male','male'),('other','other')])

the admin.py file:

from django.contrib import admin
from .forms import Person

admin.site.register(Person)

You register a Model as an admin class, not a form.

You can define a ModelAdmin class to use a custom form.

Thank you for your reply but I don’t understand what exactly I should do.
Can you explain exactly what I should do?
Django documentation causes more confusion than clarity to me.